Such language. Not that he doesn't deserve the moniker, but really.
In reading some of the information about this guy, I really doubt any armed law-abiding citizen would have been able to stop him - between the darkness, compromised night-vision (due to bright movie screen), tear gas, and the kevlar the shooter was wearing, it would have been difficult, if not impossible, to get a good shot.
I know I sure couldn't have done it. Despite your low opinion of me, I'm not foolish enough to take that kind of risk.
Of course, being a law-abiding citizen, I respect Simon Mall's right to disallow firearms, and would have either not attended the movie, or if I had, been unarmed. The shooter, obviously, did not respect private property rights.
I still wonder how he managed to get into the theater without security and/or police being alerted that someone with a rifle was traipsing through the mall. Or did he come from outside the mall? I walked into a Simon Malls-owned facility once, and within 20 feet, security was hassling me about my holster (which turned out to be empty at the time - as per their Code of Conduct, I disarmed prior to entry).